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New image size from my bro's nook, both with Roadkil and dd, is 1962934272 bytes.
Old image size from my own nook, using Roadkil, is 1958739968 bytes.
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Uhhmm...
I also used Roadkil to make a backup of a couple of refurbished Nook and they both are 1.958.739.968 bytes! I also restored using it and had no problem up to now.